Fluid operable short stroke device



March 2, 1948.

V. S. SHAW FLUID OPERABLE SHORT STROKE ,bEVIGE Filed Feb. 20, 1943 2 Sh'eets-Sheet 1 125% 3"! r I 35r' S 30 y g 33 Q Q, 20

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32 W 7 56 2 1 ATTORNEY$ 2 S heets-Sheet 2 v. s. SHAW FLUID OPERABLE SHORT STROKE DEVICE Filed Feb. 20, 1943 5: Ilifi INVENTOR VmmRSDnAv .av a I ATTORNEYS March 2, 1948.

Patented Mar. 1948 Victor 8. Shaw, Mount Gilead, Ohio, asaignor to H-P-M Development Corporation, a corporation oi Delaware Application February 20, 1843, Serial No. 476,653

11 China. (UL 24-249) This invention relates to fluid operable means,

and in particular, tofluid actuated elements with a short stroke. v I It is an object of this invention to provide simplified iiuid actuated means for use in connection with a reciprocable element to bring about a short stroke of said element. Although by no means limited to clamping or gripping devices, the invention 'is of particular.

advantage in connection with such mechanism. It is therefore, another object to create a clamping or gripping device, in which inflatable means is provided for actuating a clamping or ripping member.

Another object of this invention consists in lowing specification in connection with the accompanying drawings in which Figure l is a view, in part perspective and in part diagrammatic, showing a device in connection with which the present invention may be used.

Figure 2 is a section on an enlarged scale,

taken substantially on line 2-2, Figure s,- and showing the left hand clamping device in end elevation to more clearly disclose the relation ofthe parts.

Figure 3 is a section along the line 3-3 of Figure 2 on a smaller scale than the latter.

Figure 4 is a sectional detail view taken on the line 4-4 of Figure 2.

Figures 5 and 6 show simple applications of the principle of the present invention. Referring now to the drawings in detail and the structure of Figure l'in particular, this structure represents a stretching device comprising a aligned sections l5, l5 and l6, l6 pertaining to the clamping jaw l3 and similarly'a plurality of clamping elements I1, I 1' and I8, l8 pertaining to the clamping jaiw l4. Figure 3 illustrates the arrangement of sections l5; and it will be understood that the sections of each jaw are similarly arranged' The clamping elements l5, l5 and l8, l8 and also the clamping elements ll, i1 and l8, l8, each having suitable clamping faces, aremovable relative to each other to clamp therebetween a metal sheet I9. As will be seen from Flgure 2 illustrating a portion of the bed ID with clamping elements 15, I5 and l6, 18', the elements l5 and I5 are interconnected by cylinders 20, 28 and 2|, 2|. The members l5 and I8 may be termed the primary clamping elements, and the members I5 and- I6'. may be termed the secondary clamping element. These cylinders are located in corresponding recesses in the adjacent clamping elements and are interconnected by bolts 22, while the cylinders are heldin a predetermined distance from each other by spacing members 23. Similarly the elements I8 and. i6 are interconnected by cylinders 24, 24' and 25, 25'. 'These cylinders are interconnected by means of bolts 28 and are spaced from each other by spacing members 21. Hollow vertical bolts 28 pass between the elements l5, l5 and l8, l3 through the bed l8 and threadedly engage a T-shaped member 29. In order to lock the hollow bolts 28 with regard to the T-shaped .member 29, bolts 38 pass through the hollow :bed or frame Ill with a cylinder II in which is reciprocably mounted a ram l2. The ram I2 is preferably operable by-fluid pressure which may be supplied through suitable conduits (not shown) from pump 43. Also mounted in the bed I are clamping jaws generally designated I3 and 14. The jaw 13 may be termed the first clamping member and thecjaw l4, the second clamping member. Each clamping Jaw comprises a plurality of I individual substantially u to a fluid reservoir or bolts 28, and their lower ends engage'nuts 3|. To prevent rotation of these nuts, pins 32 are provided which extend through the nuts 3| into the T-shaped member 28. The T-shaped member 28 extends into the bed Ill and defines with the latter a. hollow chamber in which is located an expansible tube 33. Similarly the bed III defines with a reciprocable member 34 a chamber in which is located an inflatable tube 35. The reclprocable member 34 engages the adjacent clamping element I6 and i5;

To supply fluid pressure to and exhaust fluid pressure from the tubes 33 and 35, these tubes are connected with two conduits 36 and 31 respectively which conduits lead to a 4-way valve 38. Also connected to the 4-way valve 38 are two interconnected conduits 38 and 48 leadin tank 4|. The tank 4| is connected by means of a suction line 42 to a fluid pressure source such as a pump 43, the pressure side of which is connected through a conduit 44 with the 4-way valve 38. While Figure 1 shows the fluid pressure supply system only for the clamping elements I'I, I1 and I8, I3, it is, of course, understood that a similar pressure supply system is provided for the elements I5, I and I6, I6.

The operation of the device will best be understood by reference to Figure 2. This figure shows the metal sheet I9 firmly clamped between the clamping elements I5 and I6, while the tube 35 is in its inflated condition. In order to release the metal sheet I9 from the clamping elements I5 and I6, the operator shifts the 4-way valve 38 so as to connect the tube 35 through the conduit 31 with the tank 4|, while fluid pressure from the-fluid source 43 is conveyed through conduits 44 and 36 into the tube 33. Due to the inflation of the tube 33, the T-shaped member 29 will move downwardly, thereby also moving the hollow bolts 28 downwardly. In view of the engagement of the shoulder 45 of the hollow bolt 28 with an adjacent shoulder on the clamping elements I5 and I6, these clamping elements move downwardly thereby reducing the projection of the axes interconnecting the cylinders 20, 20' and 2|, 2|. Similarly the downward movement of the clamping member Iii-reduces the projection of the axes pertaining to the cylinders 24, 24 and 25, 25. Therefore, the pressure previously exerted by the clamping elements I5 and I6 on the metal sheet I9 is released so that the metal sheet I 9 may now be removed from the clamping device.

On the other hand, if the metal sheet I9 is to be clamped between the clamping elements I5 and I6, the 4-way valve 38 will beshifted so as connect the tube 33 through conduit 36 with the tank 4 I, while fluid pressure from the fluid source 43 is conveyed through the conduit 31 into the tube 35. In this way the tube 35 will be inflated and move the reciprocable member 34 upwardly. As a result thereof the member 34 moves the clamping elements I5 and I6 upwardly thereby increasing the projection between the axes of the cylinders 20, 25' and 2|, 2| and also of the axes pertaining to the cylinders 24, 24' and 25, 25'. Consequently, the clamping elements I5 and I6 are moved toward each other, thereby exerting clamping pressure upon the metal sheet I9. When the metal sheet I9 is stretched by upward movement of the ram I2, it will tend to move the clamping elements I5 and I6, thereby causing the same to exert further clamping pressure on the metal sheet. The upward movement of the clamping elements I5 and I6, and thereby the maximum clamping pressure exerted by these elements on the metal sheet I9 is dependent on the relative position of the hollow bolts 28 and the T-shaped member 29. In other words, as soon as the area 4-6 of the T-shaped member 29 engages the opposite area 41 of the bed I0, no further upward movement of the hollow bolts 28 is possible. Since bolts 28, by means of the shoulder 45, limit the upward movement of the clamping elements I5 and I6, the clamping pressure exerted by said elements on the metal sheet I9 is limited. It will, therefore, be clear that by screwing the bolts 28 out of the T-shaped member 29, greater clamping pressure can be exerted by the clamping elements I5 and I6 upon'the metal sheet I9, while by screwing the hollow .bolts 28 further into the T-shaped member 28, the maximum clamping pressure which may be exerted upon the metal sheet I6 will be reduced.

As will be clear from Figure 3, the hollow bolts 28 may be adjusted individualy so that the various clamping elements I5 and I6 may exert difierent clamping pressure on the metal sheet II along the width thereof. This is clearly illustrated in Figure 3 in which the two end clamping elements I5 are held in a lower position than the next adjacent clamping elements I5 so that the latter are adapted to exert a greater maximum clamping pressure on the metal sheet I8 than can be exerted by the outer clamping elements I5. The tubes 33 and 35 will automatically adapt themselves to the adjustment of the hollow bolts 28 for the individual clamping elements I5 and I6 pertaining thereto.

It will thus be apparent that element I5 is connected to element I5 for movement in an arcuate path thereabout and that element I6 is similarly connected to element I6. Furthermore, it is clear that the two paths intersect so that, when urged upwardly by member 34 upon inflation of tube 35, elements I5 and I6 are positively moved or urged toward each other with a force that is, neglecting friction, equal to the upward thrust multiplied by the cotangent of the angle between a line vertical to the plane of the 'clamping surface and the axis of members 21.

an expansible tube 48 is provided which is located in a member 49 and adapted to actuate a reciprocable member 50 as soon as pressure fluid is supplied to the tube 48. When thetube 48 is exhausted, the weight of the member50 will return the latter to its initial or starting position. Similarly, Figure 6 shows a cylinder 5| having reciprocably mounted therein a reciprocable member or plunger 52 which is engaged by an expansible member 53. It will be clear that as soon as pressure fluid is supplied to the expansible member 53, the member or plunger 52 will be actuated.

It will also be understood that the present invention is by no means limited to the particular structure shown in the drawings but also embraces any modifications within the scope of the appended claims.

Having thus fully described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a force-exerting device a bed having a wall, said wall having a first channel opening into one face of said wall, a second parallel channel opening into the opposite face of said wall, two plunger means each fltting a respective channel andforming chambers with the respective channels, a dilatable element in each chamber, pressure elements mounted on said bed for guided movement toward and from each other in intersecting paths away from said first channel, and positioned'to be so moved in one direction along their paths by the plunger in said first channel, whereby to press a work piece between said elements, and means on said bed, connected to be operated by said second plunger to engage and move said elements in the opposite direction along their paths as said element in said second channel is dilated.

2. In combination, a plurality of oppositely located clamping units, each of said clamping units comprising a plurality of primary and secondary clamping elements arranged side by side, each primary clamping element being movably connected with an adjacent secondary clamping element, control means for individually controlling the maximum distance between the interconnected primary andsecondary clamping elements, and a single inflatable member common to element movably interconnected, adjustable con-- trol means for adjusting relative movement between the primary element and the first clamp ing member and for limiting the maximum movement of said primary element toward said first clamping member, and inflatable means in operative engagement with the clamping members and operable'positively to bring about relative movement of said primary element and toward said first clamping member in accordance with the adjustment by said control means, said control means being adjustable independently of said inflatable means.

4. In combination, a plurality of oppositely located clamping units, each of said units comprising a plurality of individually adjustable clamping blocks, each of said blocks comprising a primary and a secondar'yclamping element, control means, means connecting said control means with said blocks and primary elements for actuating said blocks individually and for positively limiting the maximum movement of said primary elements toward each other, first inflatable means operable to bring about movement of said primary elements toward each other in accordance with the adjustment of said control means, and

second inflatable means operable to bring about movement of said primary elements away from each other, said control means being adapted to be actuated independently of said first and said second inflatable means.

5. In a clamping device, first and second spaced parallel elements, a linkage connection between said elements limiting them to relative arcuate movement in planes transverse of said elements, first means having a clamp face lying in the path of arcuate movement of an opposing clamp face of said first element, means restraining said first means and said second element against separation, actuating means including an inflatable tube, said actuating means including means for engaging said first element and urging it in its path, whereby to clamp a work piece between said faces and means connecting said actuating means to each pair of first and second elements for adjustment independently of said actuating means for individually limiting the maximum clamping pressure of each pair of cooperating first and second elements.

ting said walls, said member being positioned to engage and move said first element in said path whereby a work piece may be clamped between said face and said first element, and means adjustable independently of said inflatable device for limiting the movement of said first element toward said clamp face. i

7. In a clamp device, a bed, a first pair of parallel clamping elements having adjacent coacting clamp faces, a second pair 01' parallel clamping elements restricted to a predetermined separation on said bed, linkage means between each element of said first pair and a respective clamping element-of said second pair and constraining said clamp faces to intersecting angularly related paths, means including an inflatable device engaging and urge each element of said first pair to move in one direction along their respective paths, means including a second inflatable element engaging and adapted to move said first pair of clamping elements in the opposite direcvtion along their respective paths, and means operable independently of said inflatable elements for individually limiting the maximum movement of each pair of coacting clamping elements.

8. In combination, a frame member, a plurality of oppositely located clamping members movably carried in said frame, a first inflatable means associated with said clamping members and responsive to a pressure created therein for moving said clamping members towards one another in order to clamp a workpiece therebetween, and a second inflatable means associated with said clamping members and responsive to a pressure created therein for moving said clamping members away from one another in order to release the said workpiece therefrom, and a plurality of individually adjustable elements operatively connected to said clamping members adapted to be actuated independently of said first and second inflatable means for limiting the clamping pressure of therespective clamping members, said adjustable elements also being adapted to be actuated by said first and second inflatable means for actuating said clamping members.

9. A work-clamping device comprising movable clamping means constituted by a plurality of separate elements, reaction means co-operating therewith for work clamping, a capsule embodying a flexible wall operatively associated with, and common to, a plurality of .said separate elements of said movable clamping means, said capsule being distortable by fiexure of a flexible wall of said capsule for outward fiexure or said flexible wall eifectually to expand said capsule means and load said movable clamping means toward said reaction means.

10. In a work-clamping member, embodying at least two clamping jaws, at least one of which is movable toward and away from the other for clamping work engaged between them; a hollow capsule having a flexible face for engagement with a .pressure member operatively associated with the movable jaw means, and a pressure fluid flow connection communicating with the interior of said capsule for fiexure of said flexible face outwardly, to urge said movable jaw means toward the co-operating clamping jaw means.

11. A work-clamping device comprising movable clamping means, reaction means co-operatin therewith for work clamping, capsule means operatively associated with said movable clamping means and having a flexed wall distortable outwardly by internal pressure, and means to .ap-

emes,

ply pressure internally of said capsule means Zor outward fiexure of said flexible wall eflectually to expand sald capsule means and load said movable clamping means toward said reaction means.

VICTOR S. SHAW.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Garvey July 26, 1910 Number Number 

